## 21820 Federal Register / Vol. 76, No. 75 / Tuesday, April 19, 2011 / Proposed Rules

**PART 39—AIRWORTHINESS DIRECTIVES** 

1. The authority citation for part 39 continues to read as follows:

Authority: 49 U.S.C. 106(g), 40113, 44701.

**§ 39.13 [Amended]**



### 2. The FAA amends § 39.13 by adding the following new AD: The Boeing Company: Docket No. FAA– 2008–0415; Directorate Identifier 2007– NM–256–AD.

Comments Due Date

(a) We must receive comments by May 16,
2011.

Affected ADs

(b) None.
Applicability

(c) This AD applies to all Model 737 airplanes; certificated in any category.
Subject

(d) Air Transport Association (ATA) of America Code 27: Flight controls.

Unsafe Condition

(e) This AD results from a report of extensive corrosion of a ballscrew in the drive mechanism of the horizontal stabilizer trim actuator (HSTA). We are issuing this AD to prevent an undetected failure of the primary load path for the ballscrew in the drive mechanism of the HSTA and subsequent wear and failure of the secondary load path, which could lead to loss of control of the horizontal stabilizer and consequent loss of control of the airplane.
Compliance

(f) You are responsible for having the actions required by this AD performed within the compliance times specified, unless the actions have already been done.
Inspections, Lubrications, Repairs/ Overhauls, and Applicable Corrective Actions

(g) At the applicable compliance time and repeat intervals listed in Tables 1 and 2 of paragraph 1.E., ‘‘ Compliance, ’’ of Boeing Alert Service Bulletin 737–27A1278, Revision 1, dated January 7, 2010; or Boeing Alert Service Bulletin 737–27A1277, Revision 2, dated January 8, 2010; as applicable (depending on airplane configuration): Do the inspections, lubrications, repairs/ overhauls, installation(s), and applicable corrective actions, by accomplishing all the applicable actions specified in the Accomplishment Instructions of Boeing Alert Service Bulletin 737–27A1278, Revision 1, dated January 7, 2010; or Boeing Alert Service Bulletin 737–27A1277, Revision 2, dated January 8, 2010; as applicable; except as provided by paragraphs (g)(1) and (g)(2) of this AD.

Note 1: Boeing Alert Service Bulletin 737– 27A1278, Revision 1, dated January 7, 2010; refers to Umbra Cuscinetti Service Bulletin 07322–27–01, dated December 21, 2004; Linear Motion Service Bulletin 7901708, Revision A, or Revision B, both dated July 26, 2005; Boeing 737 Service Bulletin 27–1046, Revision 1, dated April 5, 1974; and Skytronics Service Bulletin 93004, dated September 1, 2005; as applicable; as additional sources of service information for accomplishing the applicable specified actions.

Note 2: Boeing Alert Service Bulletin 737– 27A1277, Revision 2, dated January 8, 2010; refers to Umbra Cuscinetti Service Bulletin 07322–27–01, dated December 21, 2004; as an additional source of service information for accomplishing the applicable specified actions.

(1) Where paragraph 1.E., ‘‘ Compliance, ’’ of Boeing Alert Service Bulletin 737–27A1278, Revision 1, dated January 7, 2010; or Boeing Alert Service Bulletin 737–27A1277, Revision 2, dated January 8, 2010; as applicable; specifies an initial compliance time for accomplishing the initial inspection, lubrication, or repair/overhaul, this AD requires doing the applicable initial action(s) at the later of the times specified in paragraphs (g)(1)(i) and (g)(1)(ii) of this AD.

(i) At the applicable compliance time specified in paragraph 1.E, ‘‘ Compliance, ’’ of Boeing Alert Service Bulletin 737–27A1278, Revision 1, dated January 7, 2010; or Boeing Alert Service Bulletin 737–27A1277, Revision 2, dated January 8, 2010; as applicable.

(ii) Within the applicable compliance time specified in paragraph (g)(1)(ii)(A), (g)(1)(ii)(B), or (g)(1)(ii)(C) of this AD.

(A) For the initial detailed inspection and lubrication: Within 6 months after the effective date of this AD.

(B) For the initial repair/overhaul: Within 12 months after the effective date of this AD.

(C) For the installation(s): Within 12 months after the effective date of this AD.

(2) Where Table 2 of paragraph 1.E.,

‘‘ Compliance, ’’ of Boeing Alert Service Bulletin 737–27A1277, Revision 2, dated January 8, 2010, specifies a compliance time of ‘‘ * * * within 25,000 Flight Hours since the latest horizontal stabilizer trim actuator (HSTA) Overhaul from the date of Revision 1 of this Service Bulletin * * *, ’’ this AD requires compliance within 25,000 flight hours since the last overhaul of the trim actuator of the horizontal stabilizer.
Credit for Actions Accomplished in Accordance With Previous Service Information

(h) Actions accomplished before the effective date of this AD in accordance with Boeing Alert Service Bulletins 737–27A1277, Revision 1, dated July 25, 2007; or 737– 27A1278, dated May 24, 2007; as applicable; are considered acceptable for compliance with the corresponding actions specified in this AD.

Parts Installation

(i) As of the effective date of this AD, no person may install a ballscrew assembly in the drive mechanism of the HSTA on any airplane, unless it has been inspected and modified, as applicable, in accordance with paragraph (g) of this AD. Alternative Methods of Compliance (AMOCs)

(j)(1) The Manager, Seattle Aircraft Certification Office (ACO), FAA, has the authority to approve AMOCs for this AD, if requested using the procedures found in 14 CFR 39.19. In accordance with 14 CFR 39.19, send your request to your principal inspector or local Flight Standards District Office, as appropriate. If sending information directly to the manager of the ACO, send it to the attention of the person identified in the Related Information section of this AD. Information may be e-mailed to: 9-ANMSeattle-ACO-AMOC-Requests@faa.gov

.

(2) Before using any approved AMOC, notify your appropriate principal inspector, or lacking a principal inspector, the manager of the local flight standards district office/ certificate holding district office.

(3) An AMOC that provides an acceptable level of safety may be used for any repair required by this AD if it is approved by the Boeing Commercial Airplanes Organization Designation Authorization (ODA) that has been authorized by the Manager, Seattle ACO to make those findings. For a repair method to be approved, the repair must meet the certification basis of the airplane.

Related Information

(k) For more information about this AD, contact Kelly McGuckin, Aerospace Engineer, Systems and Equipment Branch, ANM–130S, FAA, Seattle Aircraft Certification Office, 1601 Lind Avenue, SW., Renton, Washington 98057–3356; telephone (425) 917–6490; fax (425) 917–6590.

Issued in Renton, Washington, on April 13,
2011. Ali Bahrami, Manager, Transport Airplane Directorate, Aircraft Certification Service.
[FR Doc. 2011–9410 Filed 4–18–11; 8:45 am]

**BILLING CODE 4910–13–P**



### DEPARTMENT OF TRANSPORTATION

**Federal Aviation Administration**

**14 CFR Part 39**

**[Docket No. FAA–2011–0381; Directorate Identifier 2010–NM–203–AD]** 

**RIN 2120–AA64**



### Airworthiness Directives; Bombardier, **Inc. Model DHC–8–400 Series Airplanes** 

**AGENCY** 

### : Federal Aviation Administration (FAA), DOT.

**ACTION** 

### : Notice of proposed rulemaking (NPRM).

**SUMMARY** 

### : We propose to adopt a new airworthiness directive (AD) for the products listed above. This proposed AD results from mandatory continuing airworthiness information (MCAI) originated by an aviation authority of another country to identify and correct


## 21821 Federal Register / Vol. 76, No. 75 / Tuesday, April 19, 2011 / Proposed Rules

an unsafe condition on an aviation product. The MCAI describes the unsafe condition as:

Several reports have been received on failures of the main landing gear (MLG) stabilizer extension springs. A landing gear audit has confirmed that the MLG may not lock in the down-lock position with the absence of both MLG stabilizer extension springs. The loss of the locking mechanism could result in the collapse of the main landing gear.


### * * * * * The proposed AD would require actions that are intended to address the unsafe condition described in the MCAI.

**DATES** 

### : We must receive comments on this proposed AD by June 3, 2011.

**ADDRESSES** 

### : You may send comments by any of the following methods:

• Federal eRulemaking Portal: Go to http://www.regulations.gov. Follow the instructions for submitting comments.

• Fax: (202) 493–2251.

• Mail: U.S. Department of Transportation, Docket Operations, M–30, West Building Ground Floor, Room W12–140, 1200 New Jersey Avenue, SE., Washington, DC 20590.

• Hand Delivery: U.S. Department of Transportation, Docket Operations, M–30, West Building Ground Floor, Room W12–40, 1200 New Jersey Avenue, SE., Washington, DC, between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays.

For service information identified in this proposed AD, contact Bombardier, Inc., Q-Series Technical Help Desk, 123 Garratt Boulevard, Toronto, Ontario M3K 1Y5, Canada; telephone 416–375– 4000; fax 416–375–4539; e-mail thd.qseries@aero.bombardier.com; Internet http://www.bombardier.com

. You may review copies of the referenced service information at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington. For information on the availability of this material at the FAA, call 425–227–1221. Examining the AD Docket

You may examine the AD docket on the Internet at http:// www.regulations.gov; or in person at the Docket Operations office between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. The AD docket contains this proposed AD, the regulatory evaluation, any comments received, and other information. The street address for the Docket Operations office (telephone (800) 647–5527) is in the **ADDRESSES** 

### section. Comments will be available in the AD docket shortly after receipt.

**FOR FURTHER INFORMATION CONTACT** 

### : Fabio Buttitta, Aerospace Engineer, Airframe and Mechanical Systems Branch, ANE–171, FAA, New York Aircraft Certification Office, 1600 Stewart Avenue, Suite 410, Westbury, New York 11590; telephone (516) 228– 7303; fax (516) 794–5531.

**SUPPLEMENTARY INFORMATION** 

### :
Comments Invited

We invite you to send any written relevant data, views, or arguments about this proposed AD. Send your comments to an address listed under the

**ADDRESSES** 

### section. Include ‘‘Docket No. FAA–2011–0381; Directorate Identifier 2010–NM–203–AD ’’ at the beginning of your comments. We specifically invite comments on the overall regulatory, economic, environmental, and energy aspects of this proposed AD. We will consider all comments received by the closing date and may amend this proposed AD based on those comments.

We will post all comments we receive, without change, to http:// www.regulations.gov, including any personal information you provide. We will also post a report summarizing each substantive verbal contact we receive about this proposed AD.

Discussion

Transport Canada Civil Aviation (TCCA), which is the aviation authority for Canada, has issued Canadian Airworthiness Directive CF–2010–22, dated July 20, 2010 (referred to after this

as ‘‘the MCAI’’ ), to correct an unsafe condition for the specified products. The MCAI states:

Several reports have been received on failures of the main landing gear (MLG) stabilizer extension springs. A landing gear audit has confirmed that the MLG may not lock in the down-lock position with the absence of both MLG stabilizer extension springs. The loss of the locking mechanism could result in the collapse of the main landing gear.

This [TCCA] directive is to mandate the incorporation of a new maintenance task for the MLG stabilizer extension springs.


### You may obtain further information by examining the MCAI in the AD docket.

Relevant Service Information

Bombardier has issued Temporary Revision MRB–45, dated October 6, 2009 to Section 1–32, Systems/ Powerplant Maintenance Program of Part 1 of the Maintenance Review Board (MRB) Report of the Bombardier Q400 Dash 8 Maintenance Requirements Manual, PSM 1–84–7. The actions described in this service information are intended to correct the unsafe condition identified in the MCAI. FAA’s Determination and Requirements of This Proposed AD

This product has been approved by the aviation authority of another country, and is approved for operation in the United States. Pursuant to our bilateral agreement with the State of Design Authority, we have been notified of the unsafe condition described in the MCAI and service information referenced above. We are proposing this AD because we evaluated all pertinent information and determined an unsafe condition exists and is likely to exist or develop on other products of the same type design.

Differences Between This AD and the MCAI or Service Information

We have reviewed the MCAI and related service information and, in general, agree with their substance. But we might have found it necessary to use different words from those in the MCAI to ensure the AD is clear for U.S. operators and is enforceable. In making these changes, we do not intend to differ substantively from the information provided in the MCAI and related service information.

We might also have proposed different actions in this AD from those in the MCAI in order to follow FAA policies. Any such differences are highlighted in a Note within the proposed AD. Costs of Compliance

Based on the service information, we estimate that this proposed AD would affect about 65 products of U.S. registry. We also estimate that it would take about 1 work-hour per product to comply with the basic requirements of this proposed AD. The average labor rate is $85 per work-hour. Based on these figures, we estimate the cost of the proposed AD on U.S. operators to be $5,525, or $85 per product. Authority for This Rulemaking

Title 49 of the United States Code specifies the FAA’s authority to issue rules on aviation safety. Subtitle I, section 106, describes the authority of the FAA Administrator. ‘‘ Subtitle VII: Aviation Programs, ’’ describes in more detail the scope of the Agency’s authority.

We are issuing this rulemaking under the authority described in ‘‘ Subtitle VII, Part A, Subpart III, Section 44701: General requirements. ’’ Under that section, Congress charges the FAA with promoting safe flight of civil aircraft in air commerce by prescribing regulations for practices, methods, and procedures the Administrator finds necessary for safety in air commerce. This regulation


## 21822 Federal Register / Vol. 76, No. 75 / Tuesday, April 19, 2011 / Proposed Rules

is within the scope of that authority because it addresses an unsafe condition that is likely to exist or develop on products identified in this rulemaking action. Regulatory Findings

We determined that this proposed AD would not have federalism implications under Executive Order 13132. This proposed AD would not have a substantial direct effect on the States, on the relationship between the national Government and the States, or on the distribution of power and responsibilities among the various levels of government.

For the reasons discussed above, I certify this proposed regulation:

1. Is not a ‘‘ significant regulatory action’’ under Executive Order 12866;

2. Is not a ‘‘ significant rule ’’ under the DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979); and

3. Will not have a significant economic impact, positive or negative, on a substantial number of small entities under the criteria of the Regulatory Flexibility Act.

We prepared a regulatory evaluation of the estimated costs to comply with this proposed AD and placed it in the AD docket. List of Subjects in 14 CFR Part 39

Air transportation, Aircraft, Aviation safety, Incorporation by reference, Safety. The Proposed Amendment

Accordingly, under the authority delegated to me by the Administrator, the FAA proposes to amend 14 CFR part 39 as follows:

**PART 39—AIRWORTHINESS DIRECTIVES** 

1. The authority citation for part 39 continues to read as follows:

Authority: 49 U.S.C. 106(g), 40113, 44701.

**§ 39.13 [Amended]**



### 2. The FAA amends § 39.13 by adding the following new AD:
Bombardier, Inc.: Docket No. FAA–2011– 0381; Directorate Identifier 2010–NM– 203–AD.

Comments Due Date

(a) We must receive comments by June 3,
2011.

Affected ADs

(b) None.
Applicability

(c) This AD applies to Bombardier, Inc. Model DHC–8–400, –401, and –402 airplanes, certificated in any category, serial numbers 4001, 4003 and subsequent. Subject (d) Air Transport Association (ATA) of America Code 32: Landing Gear.

Reason

(e) The mandatory continuing airworthiness information (MCAI) states:

Several reports have been received on failures of the main landing gear (MLG) stabilizer extension springs. A landing gear audit has confirmed that the MLG may not lock in the down-lock position with the absence of both MLG stabilizer extension springs. The loss of the locking mechanism could result in the collapse of the main landing gear.


### * * * * *
Compliance

(f) You are responsible for having the actions required by this AD performed within the compliance times specified, unless the actions have already been done.

Actions

(g) Within 30 days after the effective date of this AD, revise the maintenance program by incorporating Task 320100–213 as specified in Bombardier Temporary Revision MRB–45, dated October 6, 2009, to Section 1–32, Systems/Powerplant Maintenance Program, of Part 1 of the Maintenance Review Board Report of the Bombardier Q400 Dash 8 Maintenance Requirements Manual, PSM 1–84–7. The initial compliance time for Task 320100–213 is within 600 flight hours after the effective date of this AD.

No Alternative Actions or Intervals

(h) After accomplishing the revision required by paragraph (g) of this AD, no alternative actions (e.g., inspections) or intervals may be used unless the actions or intervals are approved as an alternative method of compliance (AMOC) in accordance with the procedures specified in paragraph (i) of this AD.

FAA AD Differences

Note 1: This AD differs from the MCAI and/or service information as follows: No differences.

Other FAA AD Provisions

(i) The following provisions also apply to this AD:

(1) Alternative Methods of Compliance (AMOCs): The Manager, New York ACO, ANE–170, FAA, FAA, has the authority to approve AMOCs for this AD, if requested using the procedures found in 14 CFR 39.19. In accordance with 14 CFR 39.19, send your request to your principal inspector or local Flight Standards District Office, as appropriate. If sending information directly to the ACO, send it to ATTN: Program Manager, Continuing Operational Safety, FAA, New York ACO, 1600 Stewart Avenue, Suite 410, Westbury, New York 11590; telephone 516–228–7300; fax 516–794–5531. Before using any approved AMOC, notify your appropriate principal inspector, or lacking a principal inspector, the manager of the local flight standards district office/ certificate holding district office. The AMOC approval letter must specifically reference this AD.

(2) Airworthy Product: For any requirement in this AD to obtain corrective actions from a manufacturer or other source, use these actions if they are FAA-approved. Corrective actions are considered FAA-approved if they are approved by the State of Design Authority (or their delegated agent). You are required to assure the product is airworthy before it is returned to service.

Related Information

(j) Refer to MCAI Transport Canada Civil Aviation (TCCA) Airworthiness Directive CF–2010–22, dated July 20, 2010; and Bombardier Temporary Revision MRB–45, dated October 6, 2009, to Section 1–32, Systems/Powerplant Maintenance Program, of Part 1 of the Maintenance Review Board Report of the Bombardier Q400 Dash 8 Maintenance Requirements Manual, PSM 1–84–7; for related information.

Issued in Renton, Washington, on April 12,
2011. Ali Bahrami, Manager, Transport Airplane Directorate, Aircraft Certification Service.
[FR Doc. 2011–9408 Filed 4–18–11; 8:45 am]

**BILLING CODE 4910–13–P**



### DEPARTMENT OF TRANSPORTATION

**Federal Aviation Administration**

**14 CFR Part 39**

**[Docket No. FAA–2011–0312; Directorate Identifier 2010–NM–159–AD]** 

**RIN 2120–AA64**



### Airworthiness Directives; Empresa **Brasileira de Aeronautica S.A. (EMBRAER) Model EMB–135ER,**  **–135KE, –135KL, and –135LR Airplanes; and Model EMB–145,**  **–145ER, –145MR, –145LR, –145MP, and –145EP Airplanes** 

**AGENCY** 

### : Federal Aviation Administration (FAA), DOT.

**ACTION** 

### : Notice of proposed rulemaking (NPRM).

**SUMMARY** 

### : We propose to adopt a new airworthiness directive (AD) for the products listed above. This proposed AD results from mandatory continuing airworthiness information (MCAI) originated by an aviation authority of another country to identify and correct an unsafe condition on an aviation product. The MCAI describes the unsafe condition as:

This [Brazilian] AD results from reports of cracking in the firewall of the auxiliary power unit (APU). This AD is being issued to detect and correct this cracking, which could result in reduced structural integrity of the fuselage and empennage in the event that